Appearing on Conan Thursday night, Ferrell struggled to put on a happy face while promoting his new comedy The Campaign. The 45-year-old actor blamed his sorrow on none other than Kristen Stewart — who shattered the worlds of boyfriend Pattinson, 26, and Twi-hards everywhere when she was caught making out with director Rupert Sanders last month in exclusive Us Weekly photos.

"There's this actress, Kristen Stewart, OK? She goes by K-Stew. And, uh, she had a boyfriend, right? Robert Pattinson. He's R-Patz. And she cheated on him," a somber Ferrell explained to O'Brien, fighting back the tears.

"And they've broken up, and they're not gonna get back together ever. And what they had was so special, Conan!" Ferrell continued in his hilarious routine, reaching full-on heaving sobs. "You don't even know what they had! They were in love! And she just threw it all away!"

(For the record, insiders recently told Us Weekly that Pattinson is currently holed up at pal Reese Witherspoon's Ojai, Calif. ranch as he ponders his next step — and ignores calls and texts from a frantic Stewart, 22.)

As O'Brien attempted to calm down Ferrell, he snapped inconsolably: "It's not gonna be fine, EVER! Never gonna be fine! What they had was so special. You don't even know! You would never know! She is a trampire!"